sun
Definition
The sun is a star, a large, hot ball of plasma held together by its own gravity. The sun is the centre of our solar system and is the source of most of the energy on Earth.
The sun is about 93 million miles from Earth. It is a giant ball of hydrogen and helium gas that is constantly burning. The sun's energy is produced by nuclear fusion, the process of combining two or more atoms to form a heavier atom.
The sun's surface temperature is about 9941 degrees Fahrenheit (5505 degrees Celsius). The sun's core temperature is about 27 million degrees Fahrenheit (15 million degrees Celsius).
The sun is a very important part of our solar system. It provides us with light and heat, and it also helps to regulate the Earth's climate. The sun's energy is also used to power many of our technologies, such as solar cells and solar power plants.
How can the word be used?
The sun's rays provide us with light and warmth.
Different forms of the word
Noun: sun.
Adjective: solar.
Verb: to sun.
Etymology
The word "sun" comes from the Old English word "sunne", which is related to the words for "sun" in other Germanic languages, such as German "Sonne" and Dutch "zon". It was first used in English in the 7th century.
The word "solar" means "of or relating to the sun".
The word "to sun" means to expose oneself to the sun's rays.
Question
What is the sun?
AQA Science Exam Question and Answer
Question:
Explain the process of nuclear fusion occurring in the Sun and its role in generating energy. Discuss the factors that enable fusion to take place in the Sun's core and the significance of this process for sustaining life on Earth.
Answer:
Nuclear fusion is the process by which the Sun generates energy. In its core, hydrogen atoms combine to form helium through a series of fusion reactions. High temperatures and immense pressures, fueled by the Sun's gravity, create conditions where hydrogen nuclei overcome electrostatic repulsion and collide with enough force to fuse into helium.
The fusion process releases an incredible amount of energy in the form of light and heat. This energy radiates outward, providing the Sun's warmth and light that sustain life on Earth.
Two key factors enable fusion to occur in the Sun's core: temperature and pressure. The Sun's core temperature, exceeding millions of degrees Celsius, provides the kinetic energy needed for nuclei to overcome their repulsion and fuse. Additionally, the immense gravitational pressure at the core compresses the hydrogen nuclei, bringing them into close proximity for fusion.
The Sun's fusion process is essential for Earth's habitability. The energy it produces drives our climate, powers photosynthesis, and fuels the water cycle. Understanding the Sun's nuclear fusion sheds light on the mechanisms that govern our solar system and the crucial role the Sun plays in maintaining the conditions necessary for life to thrive on our planet.